37 CFR § 1.366 - Submission of maintenance fees.
(a) The patentee may pay maintenance fees and any necessary surcharges, or any person or organization may pay maintenance fees and any necessary surcharges on behalf of a patentee. A maintenance fee transmittal letter may be signed by a juristic applicant or patent owner. A patentee need not file authorization to enable any person or organization to pay maintenance fees and any necessary surcharges on behalf of the patentee.
(b) A maintenance fee and any necessary surcharge submitted for a patent must be submitted in the amount due on the date the maintenance fee and any necessary surcharge are paid. A maintenance fee or surcharge may be paid in the manner set forth in § 1.23 or by an authorization to charge a deposit account established pursuant to § 1.25. Payment of a maintenance fee and any necessary surcharge or the authorization to charge a deposit account must be submitted within the periods set forth in § 1.362 (d), (e), or (f). Any payment or authorization of maintenance fees and surcharges filed at any other time will not be accepted and will not serve as a payment of the maintenance fee except insofar as a delayed payment of the maintenance fee is accepted by the Director in an expired patent pursuant to a petition filed under § 1.378. Any authorization to charge a deposit account must authorize the immediate charging of the maintenance fee and any necessary surcharge to the deposit account. Payment of less than the required amount, payment in a manner other than that set forth in § 1.23, or in the filing of an authorization to charge a deposit account having insufficient funds will not constitute payment of a maintenance fee or surcharge on a patent. The procedures set forth in § 1.8 or § 1.10 may be utilized in paying maintenance fees and any necessary surcharges.
(c) In submitting maintenance fees and any necessary surcharges, identification of the patents for which maintenance fees are being paid must include the patent number, and the application number of the United States application for the patent on which the maintenance fee is being paid. If the payment includes identification of only the patent number (i.e., does not identify the application number of the United States application for the patent on which the maintenance fee is being paid), the Office may apply the payment to the patent identified by patent number in the payment or may return the payment.
(d) Payment of maintenance fees and any surcharges should identify the fee being paid for each patent as to whether it is the 3 1/2-, 7 1/2-, or 11 1/2-year fee, whether small entity status is being changed or claimed, the amount of the maintenance fee and any surcharge being paid, and any assigned customer number. If the maintenance fee and any necessary surcharge is being paid on a reissue patent, the payment must identify the reissue patent by reissue patent number and reissue application number as required by paragraph (c) of this section and should also include the original patent number.
(e) Maintenance fee payments and surcharge payments relating thereto must be submitted separate from any other payments for fees or charges, whether submitted in the manner set forth in § 1.23 or by an authorization to charge a deposit account. If maintenance fee and surcharge payments for more than one patent are submitted together, they should be submitted on as few sheets as possible with the patent numbers listed in increasing patent number order. If the payment submitted is insufficient to cover the maintenance fees and surcharges for all the listed patents, the payment will be applied in the order the patents are listed, beginning at the top of the listing.
(f) Notification of any change in status resulting in loss of entitlement to small entity status must be filed in a patent prior to paying, or at the time of paying, the earliest maintenance fee due after the date on which status as a small entity is no longer appropriate. See § 1.27(g).
(g) Maintenance fees and surcharges relating thereto will not be refunded except in accordance with §§ 1.26 and 1.28(a).